Bistable relay

ABSTRACT

A bistable impulse relay having a rocker member pivotally mounted to move back and forth between two terminal positions. A switch means with leaf spring contact arms is actuated by the rocker member. The rocker member being provided with permanent magnet means releasably retaining the rocker member in at least one terminal position.

United States Patent [191 Foster 1 Apr. 17, 1973 [54] BISTABLE RELAY [75] Inventor: Jack V. Foster, Fort Branch, Ind.

[7 3] Assignee: AMF lncorporatemNew York, NY.

[22] Filed: Aug. 5, 1971 [21] Appl. N0.: 169,374

[52] US. Cl ..335/170, 335/190 [51] Int. Cl. ..Hlh 9/20 [58] Field of Search ..335/l74, 170, 190,

[ 6 1 References Cited UNITED STATES PATENTS /1944 Rader ..200/67 F 10/1959 Brunicardi ..335/l 3/1966 Obszarnyetal ..335/

Primary Examiner-Harold Broome Attorney-George W. Price et a1.

[57] ABSTRACT A bistable impulse relay having a rocker member pivotally mounted to move back and forth between two terminal positions. A switch means with leaf spring contact arms is actuated by the rocker member, The rocker member being provided with permanent magnet means releasably retaining the rocker member in at least one terminal position.

11 Claims, 7 Drawing Figures PATENTED-APR17I975 13,728,651

SHEET 1 BF 2" IN NTO'R JACK V. O TER PATENTEBAPR 1 11% j 3.728.651

, 'SHEEI20F2 'INVENTOR JACK V. F0 TER I BISTABLE RELAY This invention relates generally to electrical switching and moreparticularly to an impulse type relay having two stable switching modes and which alternates from one mode to the other in response to successive pulses. I

As shown in US. Pat. No. 2,917,598 -granted Dec. 15, 1959 to .I.V. Foster et al; and assigned to the same assignee as the present application, relays of this type here-to-fore embodied one or more bistable snap switches. The over center action of the snap switches provided the stable switching modes of the relay.

It has been found that bistable snap switches have a limited life, are comparatively difficult to adjust and maintain, and are relatively expensive. It also is noted that substantial forces are required to actuate pluralities of over center devices and it is very difficult to adjust such devices to simultaneously move past center.

Accordingly, an object of the present invention is to provide an improved impulse type relay having relatively uncomplicated electrical switching means.

Another object of the present invention is to provide the foregoing relay with magnetic latching means for at least one of its two stable switching modes.

The present invention contemplates a clapper type impulse relay having a frame member, a rocker member pivotally mounted on the frame member and movable back and forth between two terminal positions in response to successive pulses operating the relay, switching means mounted on the frame member and actuated by the rocker member as it moves from one terminal position to the other, and the frame and rocker members being provided with permanent magnet means releasably retaining the rocker member in at least one terminal position.

The foregoing and other objects and advantages of the invention will appear more fully hereinafter from a consideration of the detailed description which follows, taken together with the accompanying drawings wherein several embodiments of the invention are illustrated by way of example. It is to be expressly understood, however, that the drawingsare for illustration purposes only and are not to be construed as defining the limits of the invention.

FIGS. 1 and 2 are front views of a relay made in accordance with the rocker member in different terminal positions;

FIG. 3 is a side view of the relay of FIG. 1;

FIG. 4 is a fragmentary plan view looking along the plane 4-4 ofFIG.1;

FIGS. 5, 6 and 7 are views corresponding to FIGS. 1, 2 and 4. respectively, of a relay embodying another form ofthe invention.

The switching means, as is best shown in'FIG. 3, is one simple make/break switch comprising a pair of spring contact arms disposed on one side of the relay merely to facilitate description of the invention and is not to be construed as a limitation. A relay made in accordance with the present invention could alterantively be provided with a single switch or a stack of switches on one or both sides. The number of switches and switch configuration are determined by the environment of the particular relay.

Referring now to the drawings and particularly to FIGS. 1 to 4, an impulse relay 10 is provided with a frame piece 11 having a front leg 12, a rear leg 13 with a stop portion 14, and a pair of lateral switch supporting flanges 15 and 16. An electromagnet 17 is mounted on the frame piece 11 between the legs 12 and 13 and the flanges 15 and 16.

A rocker member 20, of a suitable dielectric nonmagnetic material, is movably connected to the front limit the rocking movement of the member 20 on its pivot 19.

An armature or clapper 27, made of a magnetic material, is suitably supported by the rear leg 13 and is rotated away from the electromagnet l7 and against the stop 14 by the unsual tail spring 18. The front end of the armature 27 is provided with a pivotable L- shaped pusher 28 retained by a centering spring 29. The pusher 28 depends from the armature 27 towards the mouth of the center slot 23.

A permanent magnet 30 is connected to the front leg 12 by a bracket 31 while an L-shaped member 32, ofa suitable magnetic material, is connected to the rocker 20 in any well known manner and is provided with a flange portion 33 which cooperates with the permanent magnet 30 to retain the rocker 20 in its terminal position as shown in FIG. 2.

A switch means 35 is mounted on the lateral flange or portion 15, and is comprised of a longer spring contact arm 36, a shorter spring contact arm 37 and suitable insulation. The spring contact arm 36 is bent out of its normal plane away from arm 37, and the free end thereof extends through the lateral slot 21 thereby retaining the rocker 20 in its terminal position as shown inFIG. in FIG. The lateral flange or portion 16 and the lateral slot 22 is not used in this instance because only a single make/break switch is shown to facilitate description of the invention. It should be readily seen that a switch could be mounted on the flange 16, and a switch stack could replace any single switch as is well known in the art. It should be noted that the apex of the cam wall 26 moves from one side of center to the other side thereof as the rocker 20 moves from one terminal posi tion to another.

Referring now to FIGS. 5 to 7, the relay 40 is essentially the same as the relay 10 except for the switch means 35 and the magnetic latching member. In this instance, the spring contact arm 36 is not bent out of its normal plane and, therefore, does not bias the rocker 20 toward a terminal position.

In place of the L-shaped magnetic member 32 of the relay 10, the rocker 20 of the relay 40 is provided with a U-shaped magnetic member 45 having a pair of spaced legs or flange portions 46 and 47 each cooperating with the permanent magnet 30 to retain the rocker 20 in a different one of its terminal positions.

As shown in FIG. 1, spring contact arm 36 of the open switch means 35 is retaining the rocker 20 in one terminal position. A pulse will energize the electromagnet 17 which, due to magnetic attraction, causes the armature 27 to move against the bias of tail spring 18. This moves the pusher 28 into slot 23, against the wall 26 and progressively deeper into the slot portion 24 causing the rocker to move against the bias of the spring contact arm 36 to its other terminal position as shown in FIG. 2. The movement of the rocker 20 closes the switch means 35 and moves the flange or leg portion 33 of the member 32 into the proximity or sphere of influence of the permanent magnet 30.

At the termination of the pulse, the tail spring 18 will return the armature 27 to its original position against the stop 14. However, the magnetic latching effect of the permanent magnet 30 and the leg portion 33 of the magnetic member 32 prevents the rocker 20 from moving and the switch means 35 remains closed.

When the electromagnet 17 is energized by the next pulse, the armature 27 again will move the pusher 28 into the center slot 23. Because of the position of the apex of the wall portion 26, the pusher 28 is moved against the wall 26 and into the slot portion 25 causing the rocker to overcome the magnetic latch and to return to its position as shown in FIG. 1. This opens the switch means 35. At the termination of the pulse, the tail spring 18 causes the armature 27 to return to its original position against the stop 14. The bias of the spring contact arm 36 of the open switch means 35 holds the rocker 20 against movement.

The relay 40 in essence operates in a manner similar to the relay 10. The permanent magnet 30 and the magnetic flange 46 provide magnetic latching corresponding to the latching provided by the magnet 30 and flange 33.

Instead of the bias of spring contact arm 36, the magnet 30 and the magnetic flange 47 provide latching of the rocker 20 in its other terminal position.

Although several embodiments of the invention have been illustrated and described in detail it is to be expressly understood that the invention is not limited thereto. Various changes may be made in the design and arrangement of the parts without departing from the spirit and scope of the invention as the same will now be understood by those skilled in the art.

I claim:

1 In a switch apparatus of the impulse relay type, the combination comprising a frame,

an electromagnet with a movable armature mounted on said frame,

resilient means biasing said armature away from said electromagnet,

a rocker arm disposed adjacent said electromagnet and mounted for rocking movement about an axis, an actuating rod connected to said armature,

said rod terminating in an actuating end,

a cam surface on said rocker arm engageable by said actuating end,

the cam surface having edges providing angularly disposed surfaces which said actuating end eng means including said surfaces responsive to operation of said armature by successive energizations of said electromagnet to cause said actuating end to rock said rocker arm on its axis alternately in opposite directions between first and second terminal positions,

switch means mounted on said frame and including at least one moveable contact arm operatively associated with said rocker arm for actuation thereby,

means on said rocker arm at a location removed from said axis for engaging said movable contact arm of the switch means,

permanent magnet means and magnetic latch means one of which is associated with the rocker arm and the other of which is fixed relative to said frame at a position to permit magnetic attraction of the permanent magnetic means to releasably hold the latch means when the rocker arm is in one of said terminal positions.

2. The switch apparatus claimed in claim 1 wherein the means on the rocker arm for engaging said movable contact arm includes,

a slot in an end of said rocker arm,

said movable contact arm having a free end received within said slot.

3. The combination claimed in claim 2 wherein said movable contact arm is elongated and resilient and bent out of its normal plane to resiliently engage said slot and bias the rocker arm when it is in the other one of said terminal positions.

4. The switch apparatus claimed in claim 1 wherein said switch means includes,

at least a second contact arm shorter than the movable contact arm and disposed to always be out of engagement with the rocker arm,

the two contact arms being engaged to make contact only when the rocker arm is in one terminal position.

5. The switch apparatus claimed in claim 1 wherein said permanent magnet means and said magnetic latch means includes,

means responsive to the magnetic attraction of the peramnent magnet means for releasably restraining the rocker arm in said first terminal position and for releasably restraining the rocker arm in said second terminal position.

6. The switch apparatus claimed in claim 5 wherein one of the permanent magnet means or magnetic latching means is a U-shaped member having spaced flange portions,

the other one of said permanent magnet means or magnetic latching means being disposed between the spaced flange portions.

7. In a clapper type impulse relay switching apparatus having a frame with an electromagnet and movable armature mounted thereon, and having a pusher means movable by the armature for rocking an elongated rocker member between first and second terminal positions, said rocker member being pivotal about an axis intermediate its ends, and wherein said switching apparatus further inlcudes switch means having at least one contact arm movable between open and closed positions, improved means for moving the movable contact arm in response to the rocking of the rocker member and improved means for releasably latching the rocker member in at least one of its terminal psoitions, said improved means comprising means disposed adjacent an end of the elongated rocker member for receiving said movable contact am and for moving it between open and closed positions in response to the rocking of the rocker member between its terminal positions,

a permanent magnet and a member of magnetic material one of which is mounted on said rocker member at a location removed from said axis and the other of which is fixedly mounted relative to said frame at a location to permit magnetic attrac tion therebetween to releasably latch the rocker member in at least one terminal position.

8. The switching apparatus claimed in claim 7 wherein the means at an end of the rocker arm for receiving said movable contact arm engages said movable arm in an electrically nonconducting contact.

9. The switching apparatus claimed in claim 8 wherein either the permanent magnet or the member of magnetic material is mounted on said rocker member at or adjacent its opposite end, and

said movable contact arm is elongated and resilient and is bent out of its normal plane to resiliently paratus having a frame with switch actuating means mounted thereon, said switch actuating means includina pusher means for rocking an elongated rocker member of non magnetic dielectric material between first and second terminal positions, said rocker member being pivotal about an axis intermediate its ends, and wherein said switching apparatus further includes switch means having at least one contact arm movable between open and closed positions, improved means for moving the movable contact arm in response to the rocking of the rocker member and improved means for releasably latching the rocker member in at least one of its terminal positions, said improved means comprising a slot disposed adjacent an end of the elongated rocker member for receiving said movable contact arm and for moving it between open and closed positions in response to the rocking of the rocker member between its terminal positions, a magnet and a latch member of magnetic material one of which is mounted on said rocker member at a location removed from said axis and the other of which is fixedly mounted relative to said frame at a location to permit magnetic attraction therebetween to releasably restrain the rocker member in at least one terminal position. 

1. In a switch apparatus of the impulse relay type, the combination comprising a frame, an electromagnet with a movable armature mounted on said frame, resilient means biasing said armature away from said electromagnet, a rocker arm disposed adjacent said electromagnet and mounted for rocking movement about an axis, an actuating rod connected to said armature, said rod terminating in an actuating end, a cam surface on said rocker arm engageable by said actuating end, the cam surface having edges providing angularly disposed surfaces which said actuating end engages, means including said surfaces responsive to operation of said armature by successive energizations of said electromagnet to cause said actuating end to rock said rocker arm on its axis alternately in opposite directions between first and second terminal positions, switch means mounted on said frame and including at least one moveable contact arm operatively associated with said rocker arm for actuation thereby, means on said rocker arm at a location removed from said axis for engaging said movable contact arm of the switch means, permanent magnet means and magnetic latch means one of which is associated with the rocker arm and the other of which is fixed relative to said frame at a position to permit magnetic attraction of the permanent magnetic means to releasably hold the latch means when the rocker arm is in one of said terminal positions.
 2. The switch apparatus claimed in claim 1 wherein the means on the rocker arm for engaging said movable contact arm includes, a slot in an end of said rocker arm, said movable contact arm having a free end received within said slot.
 3. The combination claimed in claim 2 wherein said movable contact arm is elongated and resilient and bent out of its normal plane to resiliently engage said slot and bias the rocker arm when it is in the other one of said terminal positions.
 4. The switch apparatus claimed in claim 1 wherein said switch means includes, at least a second contact arm shorter than the movable contact arm and disposed to always be out of engagement with the rocker arm, the two contact arms being engaged to make contact only when the rocker arm is in one terminal position.
 5. The switch apparatus claimed in claim 1 wherein said permanent magnet means and said magnetic latch means includes, means responsive to the magnetic attraction of the peramnent magnet means for releasably restraining the rocker arm in said first terminal position and for releasably restraining the rocker arm in said secOnd terminal position.
 6. The switch apparatus claimed in claim 5 wherein one of the permanent magnet means or magnetic latching means is a U-shaped member having spaced flange portions, the other one of said permanent magnet means or magnetic latching means being disposed between the spaced flange portions.
 7. In a clapper type impulse relay switching apparatus having a frame with an electromagnet and movable armature mounted thereon, and having a pusher means movable by the armature for rocking an elongated rocker member between first and second terminal positions, said rocker member being pivotal about an axis intermediate its ends, and wherein said switching apparatus further inlcudes switch means having at least one contact arm movable between open and closed positions, improved means for moving the movable contact arm in response to the rocking of the rocker member and improved means for releasably latching the rocker member in at least one of its terminal psoitions, said improved means comprising means disposed adjacent an end of the elongated rocker member for receiving said movable contact arm and for moving it between open and closed positions in response to the rocking of the rocker member between its terminal positions, a permanent magnet and a member of magnetic material one of which is mounted on said rocker member at a location removed from said axis and the other of which is fixedly mounted relative to said frame at a location to permit magnetic attraction therebetween to releasably latch the rocker member in at least one terminal position.
 8. The switching apparatus claimed in claim 7 wherein the means at an end of the rocker arm for receiving said movable contact arm engages said movable arm in an electrically nonconducting contact.
 9. The switching apparatus claimed in claim 8 wherein either the permanent magnet or the member of magnetic material is mounted on said rocker member at or adjacent its opposite end, and said movable contact arm is elongated and resilient and is bent out of its normal plane to resiliently contact the means for receiving the contact arm and thereby resiliently bias the rocker member when the rocker member is in its second terminal position.
 10. The switching apparatus claimed in claim 9 wherein said member of magnetic material includes first and second contact portions respectively releasably engageable by the permanent magnet means when said rocker member is in its respective terminal positions.
 11. In a clapper type impulse relay switching apparatus having a frame with switch actuating means mounted thereon, said switch actuating means including pusher means for rocking an elongated rocker member of non magnetic dielectric material between first and second terminal positions, said rocker member being pivotal about an axis intermediate its ends, and wherein said switching apparatus further includes switch means having at least one contact arm movable between open and closed positions, improved means for moving the movable contact arm in response to the rocking of the rocker member and improved means for releasably latching the rocker member in at least one of its terminal positions, said improved means comprising a slot disposed adjacent an end of the elongated rocker member for receiving said movable contact arm and for moving it between open and closed positions in response to the rocking of the rocker member between its terminal positions, a magnet and a latch member of magnetic material one of which is mounted on said rocker member at a location removed from said axis and the other of which is fixedly mounted relative to said frame at a location to permit magnetic attraction therebetween to releasably restrain the rocker member in at least one terminal position. 